Quantitative Aptitude - Arithmetic Ability Questions

On a certain item profit is 120%. If the cost price increases by 10% then what will be the new profit margin (in %) if selling price remains the same?

When a number is increased by 24, it becomes 115% of itself. What is the number?

The ratio of ages of father and son is 7:2. Five years ago the product of their ages was 150. What is the age of the father?

A milkman buys milk at Rs 24 per litre. He adds 1/5 of water to it and sells the mixture at Rs 32 per litre. What will be his gain (in %)?

X can complete 5/7 part of a work in 10 days and Y can complete 3/4 part of the same work in 9 days. In how many days will both complete 13/21 part  of the total work?

A man gains 15% by selling a calculator for a certain price. If he sells it at the triple the price, then what will be the profit percentage?

In the given figure, 3 semicircles are drawn on three sides of triangle ABC. Ab = 21 cm, BC = 28 cm and AC = 35 cm. What is the area (in sq.cm) of the shaded part?

If a merchant offers a discount of 4% on the list price, then she makes a loss of 10%. What % profit or % loss will she make if she sells at a discount of 20% of the list price?